5 Popular Misconceptions Regarding Polycystic Ovary Syndrome (PCOS)

Joseph Peña, MD, FACOG

Joseph Peña, MD, FACOG has created a special five part series dispelling many of the common myths around PCOS.

Myth #1 – “If I have irregular periods, I have PCOS”.

Women with irregular menstrual periods are often unaware of the reason for their menstrual irregularity.  Many women are placed on hormonal contraceptives (i.e. birth control pills) by their gynecologist to regulate their mensetrual periods and prevent an overgrowth of the lining of the uterus that may lead to cancer if left unchecked.  Some women are told they have PCOS as this is the most common etiology for irregular menstrual periods (4-7% of women of reproductive age, ~60-85% of anovulatory women), while others are not given a specific reason for their irregular menstrual periods. 

While there is no universally accepted definition for PCOS, there are a few expert groups which have generated diagnostic criteria.  The Rotterdam Consensus Criteria (2006) requires two of the three signs/symptoms of PCOS (hyperandrogenism, irregular menstrual periods, polycystic-appearing ovaries on pelvic ultrasound) to be present for the diagnosis to be made.  The Androgen Excess Society (2006) requires hyperandrogenism plus one of the other two signs/symptoms (irregular menstrual periods, polycystic-appearing ovaries on pelvic ultrasound).  The hyperandrogenism criteria may be satisfied by either the presence of hirsutism (excessive hair growth) or elevated androgen levels, such as testosterone.  However, both criteria recommend excluding other possible causes of these signs and symptoms.  The differential diagnosis of someone with irregular menstrual periods and/or hirsutism is listed in the table below.

The proper evaluation of a woman with irregular menstrual periods and confirmation of PCOS is important because this affects treatment (e.g. combined hormonal contraceptives for PCOS, thyroid hormone replacement for hypothyroidism, corticosteroid replacement for nonclassical congenital adrenal hyperplasia, surgery for androgen-secreting tumor, etc.), as well as determining future fertility treatment (e.g. clomiphene citrate for PCOS, dopamine agonist for hyperprolactinemia, in vitro fertilization using donor oocytes for ovarian failure, etc.).  Thus, it is important for women to ask their physicians for a diagnosis for their irregular menstrual cycles.